SYE or custom driveshaft?

[2TALL1]

Wow I would have never guessed that.
I used to have an old ford with a divorced transfer case and had to time the drive lines every time after you went 4wheelin. The little input driveline had to line up with the rear driveline. Otherwise you had bad vibrations.
So are you just going to keep rotating it until you find the sweet spot?
I’m actually blown away I’ve never heard of this being an issue.
I’ve pulled mine and put new u joints in it and didn’t think twice about the clocking of it.

 

[u2slow]

Doesnt the tcase and driveshaft (yoke) have a master spline? (i forget) ...so theres only one indexing that it fits together?

You must be registered for see images attach

 

[mercdudecbr600]

Wow I would have never guessed that.
I used to have an old ford with a divorced transfer case and had to time the drive lines every time after you went 4wheelin. The little input driveline had to line up with the rear driveline. Otherwise you had bad vibrations.
So are you just going to keep rotating it until you find the sweet spot?
I’m actually blown away I’ve never heard of this being an issue.
I’ve pulled mine and put new u joints in it and didn’t think twice about the clocking of it.

What’s interesting is that almost every mechanical instruction states to mark dl position before removing. So I infer that clocking is a thing to the more initiated.

I also didnt think it mattered - and maybe it only does because my tc output shaft and/or dl is slightly bent and getting that assembly just right is what helps the vibs. This has been quite a journey!

 

[mercdudecbr600]

Doesnt the tcase and driveshaft (yoke) have a master spline? (i forget) ...so theres only one indexing that it fits together?

You must be registered for see images attach

No it doesn’t. It’s the opposite, it has a blank and the output shaft has no master spline

 

[mercdudecbr600]

story continues. After fussing and fussing (indexing), I did find a position that allowed me to get to 75mph with minimal but predictable vibration. I tried 8-10 positions. But despite my intuition I never found a spot that allowed smooth driving. I felt like I exhausted the rear driveshaft and pulled the front driveshaft. Smooth driving to 85mph.

I’ve replaced 3x’s already with a “balanced” lifetime unit, so I’m starting to suspect that I’ll have to index the front driveline. To be continued…

 

[mercdudecbr600]

Replaced my lifetime unit (trakmotive) with a new unit AGAIN. Smooth but still some minor vibration at 75mph, indexing at the front diff helped a small amount. I have noticed that with the poly front diff bushings, there is a slight "singing" from the front end - this noise isn't particularly noticeable without the front driveshaft. So either the driveshaft's cv's are making some minor vibration/harmonics or the front bushings are so rigid that it allows any harmonics to be transferred as NVH into the cabin.

Good news is that this journey is close to being over, my issue is 95% resolved. But, I'm going to take one more stab at the front driveshaft by taking an OEM shaft (with weights attached to both ends of the shafts) and rebuild the cv's with dana parts. My thinking: the shafts from factory MUST BE very well balanced. So as long as I get good cv joints, this might be the ultimate solution.

Yet again, to be continued.

 

[mercdudecbr600]

Alright. Update time. Sourced an oem unit and pulled the cv joints off.

Rear joint was very easy. Front joint had to be hammered off the shaft. And then the new one hammered back on. Packed both with good synthetic bearing grease.

Side note: The Dana front cv kit did not have the correct boot included, so I had to order one from driveshafts parts.

Haven’t put many miles on the setup yet, but very smooth up to 75mph. There might be very minor vibs at that speed but it’s now 99% smooth.

Highly recommend everyone do this (vs new driveshaft).

 

[2TALL1]

I’m glad you finally figured it out.
My front needs rebuilt bad. I bought a rebuild kit for it but haven’t gotten to it yet. Now you got me worried about the boot it’s not a Dana kit so maybe I’ll luck out.

 

[u2slow]

Side note: The Dana front cv kit did not have the correct boot included, so I had to order one from driveshafts parts.

My kit was sourced from some ATV parts supplier on ebay. (Not Dana Stuff) It seems this is a fairly generic type joint that shows up on ATVs and SxS's. Its also used on 99-03 Grand Cherokees, and perhaps others.